Most female — and some male — subway riders have horror stories of being grabbed, groped, flashed or even attacked. But only 587 incidents of sexual harassment have been reported this year.

“It’s the number one quality of life issue in the subway,” said NYPD's Transit Chief James Hall, acknowledging, “It’s an underreported crime.”

There were 564 incidents reported in 2008 and 438 arrests. This year 412 arrests have been made — 14 were registered sex offenders and 71 had prior sex offenses.

Reports rose since 2008 when the MTA kicked off a public awareness campaign with subway posters and PA announcements.

Officers are required to report the crimes when victims come forward, Hall said. But when Oraia Reid, of New Yorkers for Safe Transit, tried to report someone groping her at the West Fourth station in August, she said she was ignored.

Reid hopes to collaborate on the MTA’s campaign to include information for bystander intervention and a hot line number.

“We’re also hoping that the NYPD will review their training, so when victims do attempt to report crimes, they’ll be taken seriously,” she said.